1. Technical Field
Example embodiments of the present invention relate in general to a plasma antenna, and more particularly, to a plasma antenna which transmits a signal using plasma.
2. Related Art
An existing low-cost directive antenna has an end-fire array, dish, or horn structure for acquiring a desired beam direction and beam shape. The beam direction of an antenna is determined by the physical direction of the antenna, and the beam shape and the available frequency of the antenna are determined by the physical size and shape of a dish or a horn.
When a low-cost directive antenna is used, it is very difficult to operate the antenna at multiple frequencies while acquiring a beam shape. An array antenna generally occupies a large area, thus requiring the addition of an array to operate at multiple frequencies. A dish or horn antenna can operate at multiple frequencies using several antennas of different shapes. However, this causes interference in signal transmission between the antennas, and thus a beam width is limited.